Adjustable boring-tool holder.



W. 0. MORRIS.

ADJUSTABLE BOEING TOOL HOLDER.

APPLICATION FILED FEB. 3,1914,

- Patented Mar. 23, 1915.

mumm CZZWarrzlr By ATTORNEYS t rare WILLIAM G. MORRIS, or

EASTON, PENNSYLVANIA.

ADJUSTABLE BORING-TOOL HOLDER.

Specification of Letters Patent.

Patented llllar. 23, 1915.

Application filed February 3, 1914. Serial No. 816,239.

To all whom it may concern:

Be it known that ll, WILLIAM (J. Mortars, a citizen of the UnitedStates, and a resident of Easton, in the county of Northampton and Stateof Pennsylvania, have invented a new and Improved Adjustable Boring-ToolHolder, of which thefollowmg 1s a full, clear, and exact descript1on.

This inventionrelates to metal working machinery and has particularreference to holders for boring tools.

Among the objects of the invention 1s to provide a holderfor a boringtool providing for delicate and accurate adjustments for variouspurposes, including the facilities for resetting a tool to thePIGClSBPOSltlOIl in which it may have been set previously, and also toprovide precise degrees of ad ustment for the boring tool for jig workpurposes.

A further object of the invention is to provide improved facilities forlocking the several parts in adjusted position, all of the ad justmentsand manipulations of the device being performed in an easy, quick andreliable manner.

The foregoing and other objects of the invention will hereinafter bemore fully described and claimed and illustrated inthe drawingsforming apart of this specification in which like characters of referenceindicate corresponding parts in all the views, and in which- Figure 1 isa front elevation ofa portion of a boring machine indicating myimprovement in use; Fig. 2 is a transverse section on the line 22 ofFig. 3; Fig. 3 is a vertical section on the line 33 of Fig. 2; Fig. 1 isa transverse section on the line 44 of Fig. 2; and Fig. 5 -is a verticalview, partly in section, on the line 55 of Fig. 3.

The several parts of the device may be made of any suitable materials,and the relative sizes and proportions, as well as the general design ofthe mechanism, may be varied to a considerable extent without departingfrom the spirit of the invention hereinafter more fully set forth andspecifically claimed.

Referring to the drawings for a more specific description of theinvention, I show at 10 a fragment of a machine including a rotaryspindle 11 into which is set or fitted the shank 12 of a tool holderhead 13. The said shank is preferably made hollow, as indicated at 12,to reduce its weight, and into the lower end of said cavity is fitted anadjustment screw nut stem 14, said nut being held in place by a headlessscrew 15. A collar 16 is carried by the head 13 and serves for thepurpose of removing the head from the spindle. The lower surface or endof the head 13 is dovetailed, as shown at 13, and is also provided witha semi-cylindrical groove 13 into which the cylindrical headl t of saidadjustmentscrew nut is located.

At 17 I provide a boring bar holder adapted to be fitted into oragainst. the lower surface of the head 13 and having a tongue 17 fittedsnugly and slidably in the dovetail 13 of the head. Said bar holder isalso provided with a semi-cylindrical groove 17 complemental to thegroove 13 above described as shown especially in Figs. 3 and 4.

From what has just been stated,it will be understood that the holder 17is moved in right lines at right angles to the axisiof the tool holderhead, itbeing confined to such movements by means of the tongue anddovetail of the respective parts.

A boring bar' 18 of any suitable size, form or construction and adaptedtocarry a cutting tool 19 is adapted to be secured in the boring barholder 17 as by means of a headless set screw 20. Any suitable means maybe provided to effect the adjustment of the bar holder in the mannerabove described and control its position with respect to the tool holderhead. The means T prefer to employ for this purpose includes a screw 21having, say, twentythreads per inch, and cooperating directly with thenut 14. "The axis of the screw coincides with the axis of the grooves 13and 17 above described.

Said set screw has a shoulder 22 lying in the normal or innermostposition within the grooves of the bar holder and abutting against abearing lug 23 of the bar holder. A head 24 or knob is keyed as by meansof -a pin 25% the outer end of the screw, and

thereby the screw is fixed to the bar holder in such a manner as to beheld from longitudinal movement therein. The outer surface of thebearing lug 23 is preferably provided with a graduated scale 26indicating .inthis instance fifty subdivisions incident to each rotationof the screw. A pointer 27 is' carried by the head 24; and coiiperateswith said scale. It will be seen, therefore,

that in a device made in accordance with the above description, arotation of the screw from one scale point to another will cause theadjustment of the bar holder through exactly one-thousandthof an inch,Having thus described my invention, I 80 or for each full rotation ofthe screw 21 the bar holder will be moved with respect to the nut 14through one-twentieth of an inch.

.As' a convenient and reliable means for locking-the bar holder 17 inadjusted position in connection with the screw'21, I provide one or morelocking screws 28 having peculiarly shaped heads countersunk within thelower portion of the head 13 and having undercut notches 28 in alinementwith and corresponding to the shape of the dovetail of said head. Bytightening the bolts 28, by any suitable wrench, the heads of the boltswill tightly grip and wedge the tongue 17 of the bar holder, whereby theincident to the operation of the cutting or boring tool.

It will be understood from the foregoing description. and in connectionwith Fig. 1, that if the job 30 is to have its cavity enlarged, theadjustment of the tool holder may be effected simply by loosening thenuts 29 and then turning the adjustment screw 21 toward the left orcounter-clockwise, as viewed in Fig. 5, through as many thousandths asdesired and as indicated by the scale.

claim as new and desire to secure by Letters Patent In a device of thecharacter set forth, the combination of a head adapted to be secured infixed position, said head having a dovetail groove extending at rightangles to the axis of the head, a boring bar holder movable in rightlines along said dovetail and having a tongue extending thereinto, meansto move the bar holder in graduated amounts, and means to lock the barholder in adjusted position, said locking means including a bolt 28having a head countersunk in said first mentioned head, the head ofthebolt having a notch 28' conforming to and in alinement with the dovetailgroove and receiving the bar holder tongue, and means to tighten thebolt to cause the bar holder tongue to bind in the dovetail groove.

In testimony whereof I- have signed my name to this specification in thepresence of tw subscribing witnesses.

WILLIAM G. MORRIS.

Witnesses:

GEORGE W. RUsTAY, GERTRUDE E. Momufs.

